JP2023019350A - Terminal device, base station device, and method - Google Patents

Abstract

To provide a terminal device which can efficiently perform communication control, and provide a method, and an integrated circuit.SOLUTION: A processing unit of a terminal device performs communication using a first cell group and a second cell group. RRC message includes first setting for setting a special cell included in the second cell group. The processing unit starts random access procedure in the special cell on the basis of the first setting including resetting with synchronization, does not deactivate the second cell group when the RRC message does not include an instruction to deactivate the second cell group, and deactivates the second cell group after the random access procedure is successful when the RRC message includes the instruction to deactivate the second cell group.SELECTED DRAWING: Figure 12

Description

The present invention relates to a terminal device, base station device and method.

In the 3rd Generation Partnership Project (3GPP), which is a standardization project for cellular mobile communication systems, technical studies and standardization of cellular mobile communication systems, including radio access, core networks, services, etc., are being conducted. there is

For example, E-UTRA (Evolved Universal LTE Terrestrial Radio Access) has started technical study and standardization as Radio Access Technology (RAT) for 3.9G and 4G cellular mobile communication systems at 3GPP. . At present, 3GPP is still conducting technical studies and establishing standards for extension technologies for E-UTRA. Note that E-UTRA is also called Long Term Evolution (LTE: registered trademark), and extended technologies are sometimes called LTE-Advanced (LTE-A) and LTE-Advanced Pro (LTE-A Pro).

In addition, NR (New Radio, or NR Radio access) is under technical review and standardization as Radio Access Technology (RAT) for 5th Generation (5G) cellular mobile communication systems in 3GPP. started. At present, 3GPP is still conducting technical studies and establishing standards for NR extension technology.

3GPP TS 38.300v 16.4.0,"NR;NR and NG-RAN Overall description; Stage 2" pp10-134 3GPP TS 36.300 v16.4.0,"Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN);Overall description; Stage 2" pp19-362 3GPP TS 38.331 v16.3.1, "NR;Radio Resource Control (RRC);Protocol specifications"pp21-881 3GPP TS 36.331 v16.3.0, "Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specifications" pp25-1015 3GPP TS 37.340 v16.4.0,"Evolved Universal Terrestrial Radio Access (E-UTRA) and NR; Multi-Connectivity; Stage 2" pp7-77 3GPP TS 38.321 v16.3.0, "NR; Medium Access Control (MAC) protocol specification" pp8-152

In order to enable large-capacity data communication as an NR extension technology, there is a dual connectivity (also called multi-connectivity) technology in which one or more base station devices and terminal devices communicate using a plurality of cell groups. . In this dual connectivity, in order to perform communication in each cell group, a terminal device needs to monitor whether there is a message addressed to itself in each cell group. In order to enable the terminal device to perform low-delay communication when a large volume of data communication occurs, the terminal device must always monitor a plurality of cell groups, and there has been a problem of consuming a lot of power. Therefore, techniques for monitoring some cell groups infrequently or stopping them (deactivated cell group)
technology) was started.

An aspect of the present invention has been made in view of the circumstances described above, and an object thereof is to provide a terminal device, a base station device, a method, and an integrated circuit capable of efficiently performing communication control.

In order to achieve the above object, one aspect of the present invention takes the following measures. That is, one aspect of the present invention is a terminal device that communicates with a base station device, comprising: a receiving unit that receives an RRC message from the base station device; group and a second cell group are used to communicate, the RRC message includes a first configuration for configuring a special cell included in the second cell group, and the processing unit performs the first includes reconfiguration with synchronization, the processing unit initiates a random access procedure in the special cell, and causes the RRC message to deactivate the second cell group. does not include an instruction to deactivate the second cell group, and the processing unit includes an instruction to deactivate the second cell group in the RRC message. case, the terminal device deactivates the second cell group after the random access procedure is successful.

Further, one aspect of the present invention is a base station apparatus that communicates with a terminal device, comprising: a transmission unit that transmits an RRC message to the terminal device; and a second cell group, wherein the RRC message includes a first setting for setting a special cell included in the second cell group, and the processing unit performs communication using the first Based on the configuration including reconfiguration with synchronization, causing the terminal device to initiate a random access procedure in the special cell, the processing unit includes the second cell group in the RRC message. When the instruction for deactivation is not included, the processing unit does not instruct the terminal device to deactivate the second cell group, and the processing unit adds the second cell group to the RRC message. a base that instructs the terminal device to deactivate the second cell group after the random access procedure is successful, if the instruction to deactivate the second cell group is included station equipment.

One aspect of the present invention is a method for a terminal device that communicates with a base station device, which receives an RRC message from the base station device and performs communication using a first cell group and a second cell group. and the RRC message includes a first configuration that configures a special cell included in the second cell group, and based on the fact that the first configuration includes reconfiguration with synchronization, the starting a random access procedure in a special cell and not deactivating the second cell group if the RRC message does not include an indication to deactivate the second cell group; A method of deactivating the second cell group after the random access procedure is successful if an RRC message includes an instruction to deactivate the second cell group.

Another aspect of the present invention is a method for a base station apparatus that communicates with a terminal apparatus, wherein an RRC message is transmitted to the terminal apparatus and communication is performed using a first cell group and a second cell group. and the RRC message includes a first configuration that configures a special cell included in the second cell group, and based on the fact that the first configuration includes reconfiguration with synchronization, the For the terminal device to initiate a random access procedure in the special cell, and if the RRC message does not include an instruction to deactivate the second cell group, for the terminal device to perform the second If there is no indication to deactivate the second cell group and the RRC message includes an indication to deactivate the second cell group, after the random access procedure is successful, A method of instructing the terminal device to deactivate the second cell group.

In addition, these generic or specific aspects may be realized by systems, devices, methods, integrated circuits, computer programs, or recording media. may be realized by any combination of

ADVANTAGE OF THE INVENTION According to one aspect of the present invention, a terminal device, a base station device, a method, and an integrated circuit can implement efficient communication control processing.

1 is a schematic diagram of a communication system according to an embodiment of the invention; FIG. A diagram of an example of the E-UTRA protocol configuration according to an embodiment of the present invention. The figure of an example of the NR protocol structure based on embodiment of this invention. The figure which shows an example of the flow of the procedure for various settings in RRC which concerns on embodiment of this invention. The block diagram which shows the structure of the terminal device in embodiment of this invention. 1 is a block diagram showing the configuration of a base station apparatus according to an embodiment of the present invention; FIG. An example of ASN.1 description included in a message regarding reconfiguration of an RRC connection in NR according to an embodiment of the present invention. 1 is an example of ASN.1 description included in a message regarding RRC connection reconfiguration in E-UTRA according to an embodiment of the present invention. An example of processing related to inactivation of SCG in the embodiment of the present invention. An example of processing related to activation of SCG in the embodiment of the present invention. An example of processing related to inactivation of SCG in the embodiment of the present invention. An example of processing related to reconfiguration with synchronization and deactivation of SCG in the embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

LTE (and LTE-A, LTE-A Pro) and NR may be defined as different Radio Access Technologies (RATs). NR may also be defined as a technology included in LTE. LTE may also be defined as a technology included in NR. Also, LTE that can be connected by NR and Multi Radio Dual connectivity (MR-DC) may be distinguished from conventional LTE. Also, LTE using 5GC for the core network may be distinguished from conventional LTE using EPC for the core network. Note that conventional LTE may be LTE that does not implement the technology standardized after Release 15 of 3GPP. Embodiments of the present invention may be applied to NR, LTE and other RATs. Although the following description uses terminology related to LTE and NR, embodiments of the present invention may be applied in other technologies using other terminology. Also, the term E-UTRA in the embodiments of the present invention may be replaced with the term LTE, and the term LTE may be replaced with the term E-UTRA.

In addition, in the embodiment of the present invention, the name of each node and entity when the radio access technology is E-UTRA or NR, and the processing in each node and entity will be described. It may be used for other radio access technologies. The name of each node or entity in the embodiment of the present invention may be another name.

FIG. 1 is a schematic diagram of a communication system according to an embodiment of the invention. It should be noted that the functions of each node, radio access technology, core network, interface, etc. described using FIG. 1 are part of the functions closely related to the embodiment of the present invention, and may have other functions.

E-UTRA 100 may be a radio access technology. E-UTRA 100 may also be the air interface between UE 122 and eNB 102 . The air interface between UE 122 and eNB 102 may be called Uu interface. The eNB (E-UTRAN Node B) 102 may be a base station device of the E-UTRA 100. The eNB 102 may have the E-UTRA protocol described below. The E-UTRA protocol may consist of an E-UTRA user plane (User Plane: UP) protocol described later and an E-UTRA control plane (Control Plane: CP) protocol described later. eNB 102 may terminate E-UTRA User Plane (UP) and E-UTRA Control Plane (CP) protocols for UE 122 . A radio access network composed of eNBs may be called E-UTRAN.

EPC (Evolved Packet Core) 104 may be a core network. Interface 112 is the interface between eNB 102 and EPC 104 and may be referred to as the S1 interface. Interface 112 may include a control plane interface through which control signals pass, and/or a user plane interface through which user data passes. The control plane interface of interface 112 may terminate at a Mobility Management Entity (MME; not shown) within EPC 104 . A user plane interface of interface 112 may terminate at a serving gateway (S-GW; not shown) within EPC 104 . The control plane interface of interface 112 may be called the S1-MME interface. The user plane interface of interface 112 may be called the S1-U interface.

Note that one or more eNBs 102 may be connected to EPC 104 via interface 112 . There may be an interface between multiple eNBs 102 that connect to the EPC 104 (not shown). An interface between multiple eNBs 102 connected to an EPC 104 may be called an X2 interface.

NR106 may be a radio access technology. NR 106 may also be the air interface between UE 122 and gNB 108 . The air interface between UE 122 and gNB 108 may be called the Uu interface. A gNB (g Node B) 108 may be the base station equipment of the NR 106 . gNB108 may have the NR protocol described below. The NR protocol may consist of an NR User Plane (UP) protocol, which will be described later, and an NR Control Plane (CP) protocol, which will be described later. gNB 108 may terminate NR User Plane (UP) and NR Control Plane (CP) protocols for UE 122 .

5GC110 may be the core network. Interface 116 is the interface between gNB 108 and 5GC 110 and may be called the NG interface. Interface 116 may include a control plane interface through which control signals pass, and/or a user plane interface through which user data passes. The control plane interface of interface 116 may terminate at an Access and Mobility Management Function (AMF; not shown) within 5GC 110 . The user plane interface of interface 116 may terminate at a User Plane Function (UPF: not shown) within 5GC 110 . The control plane interface of interface 116 may be called the NG-C interface. The user plane interface of interface 116 may be called the NG-U interface.

Note that one or more gNBs 108 can be connected to the 5GC 110 via interface 116 . There may be interfaces between gNBs 108 that connect to the 5GC 110 (not shown). An interface between multiple gNBs 108 connected to a 5GC 110 can be called an Xn interface.

The eNB102 may have the ability to connect to the 5GC110. The eNB 102 that has the function of connecting to the 5GC 110 can be called ng-eNB. Interface 114 is the interface between eNB102 and 5GC110, NG
You can call it an interface. Interface 114 may include a control plane interface through which control signals pass, and/or a user plane interface through which user data passes. The control plane interface of interface 114 may terminate at an Access and Mobility Management Function (AMF; not shown) within 5GC 110 . The user plane interface of interface 114 may terminate at a User Plane Function (UPF: not shown) within 5GC 110 . The control plane interface of interface 114 may be called the NG-C interface. The user plane interface of interface 114 may be called the NG-U interface. A radio access network composed of ng-eNBs or gNBs may be referred to as NG-RAN. NG-RAN, E-UTRAN, eNB, ng-eNB, gNB, etc. may simply be referred to as networks.

Note that one or more eNBs 102 can be connected to the 5GC 110 via interface 114 . There may be an interface between multiple eNBs 102 that connect to the 5GC 110 (not shown). An interface between multiple eNBs 102 connected to a 5GC 110 may be called an Xn interface. Also, the eNB 102 connected to the 5GC 110 and the gNB 108 connected to the 5GC 110 can be connected via an interface 120 . The interface 120 between the eNB 102 connected to the 5GC 110 and the gNB 108 connected to the 5GC 110 can be called the Xn interface.

gNB108 may have the ability to connect to EPC104. A gNB 108 with the ability to connect to an EPC 104 may be called an en-gNB. Interface 118 is the interface between gNB 108 and EPC 104 and may be referred to as the S1 interface. Interface 118 may include a user plane interface through which user data passes. A user plane interface of interface 118 may terminate at an S-GW (not shown) within EPC 104 . The user plane interface of interface 118 may be called the S1-U interface. Also, the eNB 102 connected to the EPC 104 and the gNB 108 connected to the EPC 104 can be connected by an interface 120 . The interface 120 between the eNB 102 connected to the EPC 104 and the gNB 108 connected to the EPC 104 may be called the X2 interface.

Interface 124 is the interface between EPC 104 and 5GC 110 and may be an interface through CP only, UP only, or both CP and UP. Also, some or all of interfaces 114, 116, 118, 120, 124, etc. may not be present depending on the communication system provided by the carrier.

UE 122 may be a terminal device capable of receiving broadcast information and paging messages transmitted from eNB 102 and/or gNB 108 . Also, UE 122 may be a terminal device capable of wireless connection with eNB 102 and/or gNB 108 . Also, the UE 122 may be a terminal device capable of establishing a wireless connection with the eNB 102 and a wireless connection with the gNB 108 at the same time. UE 122 may have E-UTRA and/or NR protocols. Note that the wireless connection may be a Radio Resource Control (RRC) connection.

When UE 122 communicates with eNB 102 and/or gNB 108, a radio connection may be established by establishing a radio bearer (RB) between UE 122 and eNB 102 and/or gNB 108. A radio bearer used in the CP may be called a signaling radio bearer (SRB). A radio bearer used for UP may also be called a data radio bearer (DRB Data Radio Bearer). Each radio bearer can be assigned a radio bearer identity (ID). The SRB radio bearer identity may be called an SRB identity (SRB ID). The DRB radio bearer identity may be called a DRB identity (DRB ID).

UE 122 may also be a terminal device capable of connecting to EPC 104 and/or 5GC 110 via eNB 102 and/or gNB 108 . When the connection destination core network of eNB 102 and/or gNB 108 with which UE 122 communicates is EPC 104, each DRB established between UE 122 and eNB 102 and/or gNB 108 further passes through EPC 104. (Evolved Packet System) May be uniquely associated with a bearer. Each EPS bearer can be identified by an EPS bearer identifier (Identity, or ID). Also, the same QoS may be guaranteed for data such as IP packets and Ethernet (registered trademark) frames passing through the same EPS bearer.

In addition, when the connection destination core network of eNB102 and/or gNB108 with which UE122 communicates is 5GC110, each DRB established between UE122 and eNB102 and/or gNB108 is further established within 5GC110. may be associated with one of the PDU (Packet Data Unit) sessions. There may be one or multiple QoS flows in each PDU session. Each DRB may be mapped to one or more QoS flows or not to any QoS flows. Each PDU session can be identified with a PDU session identifier (Identity, Identifier, or ID). Each QoS flow may also be identified with a QoS flow identifier (Identity, Identifier, or ID). Also, the same QoS may be guaranteed for data such as IP packets and Ethernet frames passing through the same QoS flow.

EPC 104 may not have PDU sessions and/or QoS flows. Also, 5GC110 does not need to have an EPS bearer. When UE 122 is connected to EPC 104, UE 122 has information of EPS bearers, but may not have information within PDU sessions and/or QoS flows. Also, when the UE 122 is connected to the 5GC 110, the UE 122 may have information in PDU sessions and/or QoS flows, but not EPS bearer information.

In the following description, eNB 102 and/or gNB 108 are also simply referred to as base station apparatuses, and UE 122 is simply referred to as terminal apparatus or UE.

FIG. 2 is a diagram of an example E-UTRA protocol architecture according to an embodiment of the present invention. Also, FIG. 3 is a diagram of an example of the NR protocol configuration according to the embodiment of the present invention. Note that the functions of each protocol described using FIG. 2 and/or FIG. 3 are part of the functions closely related to the embodiment of the present invention, and may have other functions. In addition, in the embodiment of the present invention, an uplink (UL) may be a link from a terminal device to a base station device. Also, in the embodiments of the present invention, the downlink (DL) may be a link from the base station apparatus to the terminal apparatus.

FIG. 2(A) is a diagram of the E-UTRA User Plane (UP) protocol stack. The E-UTRAN UP protocol may be the protocol between UE 122 and eNB 102, as shown in FIG. 2(A). That is, the E-UTRAN UP protocol may be a protocol that terminates at the eNB 102 on the network side. As shown in FIG. 2(A), the E-UTRA user plane protocol stack includes a PHY (Physical layer) 200 that is a radio physical layer (radio physical layer), a MAC (Medium Access Control) 202, RLC (Radio Link Control) 204 which is a radio link control layer (radio link control layer), and PDCP (Packet Data Convergence Protocol) 206 which is a packet data convergence protocol layer (packet data convergence protocol layer). good to be

FIG. 3(A) is a diagram of the NR user plane (UP) protocol stack. As shown in Fig. 3(A), NR
The UP protocol may be the protocol between UE 122 and gNB 108. That is, the NR UP protocol may be a protocol that terminates at the gNB 108 on the network side. As shown in FIG. 3(A), the E-UTRA user plane protocol stack consists of PHY 300, which is a radio physical layer, MAC 302, which is a medium access control layer, RLC 304, which is a radio link control layer, and PDCP 306, which is a packet data convergence protocol layer. , and SDAP (Service Data Adaptation Protocol) 310, which is a service data adaptation protocol layer.

FIG. 2(B) is a diagram of the E-UTRA Control Plane (CP) protocol architecture. As shown in FIG. 2B, in the E-UTRAN CP protocol, RRC (Radio Resource Control) 208, which is a radio resource control layer (radio resource control layer), may be a protocol between UE 122 and eNB . That is, RRC 208 may be a protocol that terminates at eNB 102 on the network side. Also, in the E-UTRAN CP protocol, NAS (Non Access Stratum) 210, which is a non-AS (Access Stratum) layer (non-AS layer), may be a protocol between UE 122 and MME. That is, the NAS 210 may be a protocol that terminates at the MME on the network side.

FIG. 3(B) is a diagram of the NR control plane (CP) protocol architecture. As shown in FIG. 3(B), in the NR CP protocol, the radio resource control layer RRC 308 may be the protocol between the UE 122 and the gNB 108. That is, RRC 308 may be a protocol that terminates at gNB 108 on the network side. Also in the E-UTRAN CP protocol, the non-AS layer NAS 312 may be the protocol between the UE 122 and AMF. That is, the NAS 312 may be a protocol that terminates with AMF on the network side.

Note that the AS (Access Stratum) layer may be a layer that terminates between the UE 122 and the eNB 102 and/or the gNB 108. That is, the AS layer is a layer including part or all of PHY200, MAC202, RLC204, PDCP206 and RRC208 and/or a layer including part or all of PHY300, MAC302, RLC304, PDCP306, SDAP310 and RRC308. good

In the embodiments of the present invention, PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC ( RRC layer) and NAS (NAS layer) are sometimes used. In this case, PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), and NAS (NAS layer) are the PHY (PHY layer) of the E-UTRA protocol. ), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), NAS (NAS layer), NR protocol, PHY (PHY layer), MAC (MAC layer), RLC (RLC layer), PDCP (PDCP layer), RRC (RRC layer), NAS (NAS layer). Also, the SDAP (SDAP layer) may be the SDAP (SDAP layer) of the NR protocol.

Further, in the embodiment of the present invention, when distinguishing between E-UTRA protocol and NR protocol, PHY 200, MAC 202, RLC 204, PDCP 206, and RRC 208 are respectively defined as PHY for E-UTRA or PHY for LTE, E-UTRA MAC for LTE or MAC for LTE, RLC for E-UTRA or RLC for LTE, PDCP for E-UTRA or PDCP for LTE, and RRC for E-UTRA or RRC for LTE. PHY200, MAC202, RLC204, PDCP206, and RRC208 are respectively E-UTRA PHY or LTE PHY, E-UTRA MAC or LTE MAC, E-UTRA RLC or LTE RLC, E-UTRA PDCP or LTE PDCP, and E-UTRA It may also be described as RRC or LTE RRC. Also, when distinguishing between the E-UTRA protocol and the NR protocol, PHY 300, MAC 302, RLC 304, PDCP 306, and RRC 308 are called PHY for NR, MAC for NR, RLC for NR, RLC for NR, and RRC for NR, respectively. There is also a thing. PHY 200, MAC 302, RLC 304, PDCP 306, and RRC 308 may also be described as NR PHY, NR MAC, NR RLC, NR PDCP, NR RRC, etc., respectively.

Entities in the AS layer of E-UTRA and/or NR are described. An entity that has some or all of the functionality of the MAC layer may be called a MAC entity. An entity that has some or all of the functionality of the RLC layer may be called an RLC entity. An entity that has some or all of the functions of the PDCP layer may be called a PDCP entity. An entity that has some or all of the functionality of the SDAP layer may be called an SDAP entity. An entity that has some or all of the functionality of the RRC layer may be called an RRC entity. The MAC entity, RLC entity, PDCP entity, SDAP entity, and RRC entity may be replaced with MAC, RLC, PDCP, SDAP, and RRC, respectively.

Data provided to lower layers from MAC, RLC, PDCP, SDAP and/or MAC, RLC, PDC
The data provided from lower layers to P and SDAP may be called MAC PDU (Protocol Data Unit), RLC PDU, PDCP PDU and SDAP PDU, respectively. In addition, MAC SDU (Service Data Unit) and RLC SDU are used for data provided from upper layers to MAC, RLC, PDCP, and SDAP and/or data provided from MAC, RLC, PDCP, and SDAP to upper layers, respectively. , PDCP SDU, and SDAP SDU. A segmented RLC SDU may also be called an RLC SDU segment.

An example of PHY functions will be described. The PHY of the terminal device may have a function of receiving data transmitted from the PHY of the base station device via a downlink (DL) physical channel. The PHY of the terminal device may have the capability of transmitting data to the PHY of the base station device via an uplink (UL) physical channel. A PHY may be connected to a high-level MAC via a Transport Channel. The PHY may pass data to the MAC over transport channels. The PHY can also be provided with data from the MAC over the transport channel. A Radio Network Temporary Identifier (RNTI) can be used in the PHY to identify various control information.

Here, the physical channel will be explained.

Physical channels used for wireless communication between the terminal apparatus and the base station apparatus may include the following physical channels.

PBCH (Physical Broadcast CHannel)
PDCCH (Physical Downlink Control CHannel)
PDSCH (Physical Downlink Shared CHannel)
PUCCH (Physical Uplink Control CHannel)
PUSCH (Physical Uplink Shared CHannel)
PRACH (Physical Random Access CHannel)

The PBCH may be used to broadcast system information required by terminals.

Also, in NR, the PBCH may be used to report the time index (SSB-Index) within the period of a block of synchronization signals (also called SS/PBCH block).

The PDCCH may be used to transmit (or carry) downlink control information (DCI) in downlink radio communication (radio communication from a base station apparatus to a terminal apparatus). Here, one or more DCIs (which may be referred to as DCI formats) may be defined for transmission of downlink control information. That is, a field for downlink control information can be defined as DCI and mapped to information bits. A PDCCH can be sent in a PDCCH candidate. A terminal can monitor a set of PDCCH candidates in a serving cell. Monitoring the set of PDCCH candidates may mean attempting to decode the PDCCH according to a certain DCI format. The DCI format may be used for PUSCH scheduling in the serving cell. PUSCH may be used for transmission of user data, transmission of RRC messages to be described later, and the like.

PUCCH may be used to transmit uplink control information (UCI) in uplink radio communication (radio communication from a terminal device to a base station device). Here, the uplink control information may include channel state information (CSI: Channel State Information) used to indicate the state of the downlink channel. Also, the uplink control information may include a scheduling request (SR: Scheduling Request) used to request UL-SCH (UL-SCH: Uplink Shared CHannel) resources. Also, the uplink control information may include HARQ-ACK (Hybrid Automatic Repeat reQuest ACKnowledgement).

The PDSCH may be used for transmission of downlink data (DL-SCH: Downlink Shared CHannel) from the MAC layer. In addition, PDSCH may be used for transmission of system information (SI), random access response (RAR), etc. in the case of downlink.

PUSCH may be used to transmit HARQ-ACK and/or CSI together with uplink data (UL-SCH: Uplink Shared CHannel) or uplink data from the MAC layer. PUSCH may also be used to transmit CSI only, or HARQ-ACK and CSI only. That is, PUSCH may be used to transmit UCI only. PDSCH or PUSCH may also be used to transmit RRC signaling (also referred to as RRC messages) and MAC control elements. Here, in the PDSCH, RRC signaling transmitted from the base station apparatus may be signaling common to multiple terminal apparatuses within the cell. Also, the RRC signaling transmitted from the base station apparatus may be signaling dedicated to a certain terminal apparatus (also referred to as dedicated signaling). That is, terminal device-specific (UE-specific) information may be transmitted using signaling dedicated to a certain terminal device. PUSCH may also be used to transmit UE capabilities in the uplink.

PRACH may be used to transmit a random access preamble. PRACH is used to indicate initial connection establishment procedures, handover procedures, connection re-establishment procedures, synchronization (timing adjustments) for uplink transmissions, and requests for UL-SCH resources. may

An example of MAC functions will be described. A MAC may be referred to as a MAC sublayer. The MAC may have functionality for mapping various logical channels (Logical Channels) to corresponding transport channels. A logical channel may be identified by a logical channel identifier (Logical Channel Identity, or Logical Channel ID). The MAC may be connected with the upper RLC by a logical channel (logical channel). Logical channels can be divided into control channels for transmitting control information and traffic channels for transmitting user information according to the type of information to be transmitted. Logical channels may also be divided into uplink logical channels and downlink logical channels. The MAC may be capable of multiplexing MAC SDUs belonging to one or more different logical channels and providing them to the PHY. The MAC may also have the capability of demultiplexing the MAC PDUs provided by the PHY and providing them to upper layers via the logical channel to which each MAC SDU belongs. Also, the MAC may have a function of performing error correction through HARQ (Hybrid Automatic Repeat reQuest). The MAC may also have a Scheduling Report (SR) function that reports scheduling information. The MAC may have the ability to prioritize between terminals using dynamic scheduling. Also, the MAC may have a function of performing priority processing between logical channels within one terminal device. The MAC may have the capability of prioritizing overlapping resources within one terminal device. E-UTRA MAC may have the capability to identify Multimedia Broadcast Multicast Services (MBMS). The NR MAC may also have the ability to identify a Multicast Broadcast Service (MBS). A MAC may have the ability to select a transport format. MAC has a function of performing discontinuous reception (DRX) and/or discontinuous transmission (DTX: discontinuous transmission), a function of executing random access (RA) procedure, notifying information of transmittable power, power A headroom report (Power Headroom Report: PHR) function, a buffer status report (BSR) function that notifies the amount of data in the transmission buffer, etc. may be provided. The NR MAC may have a Bandwidth Adaptation (BA) function. Also, the MAC PDU format used in E-UTRA MAC and the MAC PDU format used in NR MAC may be different. Also, the MAC PDU may include a MAC control element (MAC control element: MAC CE), which is an element for performing control in MAC.

A random access procedure performed by a MAC will be described. The random access procedure can be initiated by PDCCH order, MAC entity or RRC. Only one random access procedure can be in progress at one MAC entity at a time. When initiating a random access procedure in a serving cell, the MAC entity of the terminal may perform some or all of (A) through (H) below.
(Processing RA)
(A) Flush the Msg3 buffer.
(B) Flush the MSGA buffer.
(C) Set the preamble transmission counter (PREAMBLE_TRANSMISSION_COUNTER) to 1.
(D) Set the preamble power ramping counter (PREAMBLE_POWER_RAMPING_COUNTER) to 1.
(E) Set preamble backoff (PREAMBLE_BACKOFF) to 0 ms.
(F) Set the power offset for 2-step RA (POWER_OFFSET_2STEP_RA) to 0 dB.
(G) Select a carrier for performing a random access procedure and set the maximum transmit power (PCMAX) on the selected carrier.
(H) If BWP is set in the terminal device, perform part or all of the processing (BRA) described later.

Here, the preamble transmission counter (PREAMBLE_TRANSMISSION_COUNTER) may be a counter for counting the number of times the terminal device has transmitted the preamble. Also, the preamble power ramping counter (PREAMBLE_POWER_RAMPING_COUNTER) may be a counter for counting the number of times the terminal device performs power ramping. Power ramping may refer to the operation of increasing transmission power when a terminal device retransmits a preamble. Also, the preamble backoff (PREAMBLE_BACKOFF) may be a parameter used by the terminal to select a backoff time when the random access procedure is not yet completed. Also, the power offset for 2-step RA (POWER_OFFSET_2STEP_RA) may be a parameter used by the terminal device to set the transmission power of the preamble during 2-step RA.

The random access procedure is successfully completed (successfully completed) means that the UE contention resolution identity (UE Contention Resolution Identity) included in the MAC CE received by the terminal device matches the CCCH SDU transmitted in message 3 (Msg3). Being there is fine. Also, the success of the random access procedure may mean that the MAC CE transmitted by the terminal device includes its own C-RNTI and that the PDCCH associated with this C-RNTI is received. Also, when the random access procedure is successful, the MAC entity of the terminal device may perform (A) and/or (B) below.
(A) Destroy all explicitly signaled Random Access Resources.
(B) Flush the HARQ buffer used for transmitting MAC PDUs contained in the Msg3 buffer and the MSGA buffer.

Uplink (UL) and/or downlink (DL) logical channels used in E-UTRA and/or NR will be described.

BCCH (Broadcast Control Channel) may be a downlink logical channel for broadcasting control information such as system information (SI).

PCCH (Paging Control Channel) may be a downlink logical channel for carrying paging messages.

A CCCH (Common Control Channel) may be a logical channel for transmitting control information between a terminal device and a base station device. CCCH may be used when the terminal does not have an RRC connection. CCCH may also be used between a base station and multiple terminals.

DCCH (Dedicated Control Channel) is a logical channel for transmitting dedicated control information in a one-to-one (point-to-point) bi-directional manner between a terminal device and a base station device. It's fine. Dedicated control information may be control information dedicated to each terminal device. DCCH may be used when a terminal device has an RRC connection.

A DTCH (Dedicated Traffic Channel) may be a logical channel for transmitting user data on a point-to-point basis between a terminal device and a base station device. A DTCH may be a logical channel for transmitting dedicated user data. Dedicated user data may be user data dedicated to each terminal device. DTCH may exist in both uplink and downlink.

Uplink mapping between logical channels and transport channels in E-UTRA and/or NR is described.

A CCCH may be mapped to an Uplink Shared Channel (UL-SCH), which is an uplink transport channel.

The DCCH may be mapped to an Uplink Shared Channel (UL-SCH), which is an uplink transport channel.

DTCH can be mapped to UL-SCH (Uplink Shared Channel), which is an uplink transport channel.

Downlink logical channel and transport channel mapping in E-UTRA and/or NR will be described.

The BCCH may be mapped to a downlink transport channel, BCH (Broadcast Channel) and/or DL-SCH (Downlink Shared Channel).

The PCCH may be mapped to a PCH (Paging Channel), which is a downlink transport channel.

A CCCH may be mapped to a Downlink Shared Channel (DL-SCH), which is a downlink transport channel.

A DCCH may be mapped to a Downlink Shared Channel (DL-SCH), which is a downlink transport channel.

The DTCH may be mapped to a Downlink Shared Channel (DL-SCH), which is a downlink transport channel.

An example of RLC functions will be described. RLC may be referred to as an RLC sublayer. The E-UTRA RLC may have a function of segmenting and/or concatenating data provided from the upper layer PDCP and providing the data to the lower layer. The E-UTRA RLC may have the capability to reassemble and re-order data provided by lower layers and provide it to upper layers. The NR RLC may have a function of adding a sequence number independent of the sequence number added by PDCP to the data provided by PDCP of the upper layer. Also, the NR RLC may have a function of segmenting data provided from PDCP and providing it to lower layers. Also, the NR RLC may have a function of reassembling data provided from lower layers and providing the reassembled data to upper layers. RLC may also have data retransmission and/or automatic repeat reQuest (ARQ) capabilities. Also, RLC may have a function of performing error correction by ARQ. The control information sent from the RLC receiving side to the transmitting side in order to perform ARQ, indicating data that needs to be retransmitted, can be called a status report. Also, the status report transmission instruction sent from the RLC transmitting side to the receiving side can be called a poll. RLC may also have a function to detect data duplication. RLC may also have a function of data discarding. RLC may have three modes: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). The TM does not divide the data received from the upper layer, and does not need to add an RLC header. A TM RLC entity is a uni-directional entity and may be configured as a transmitting TM RLC entity or as a receiving TM RLC entity. The UM divides and/or combines the data received from the upper layer, adds an RLC header, etc., but does not need to perform data retransmission control. A UM RLC entity may be a unidirectional entity or a bi-directional entity. If the UM RLC entity is a unidirectional entity, the UM RLC entity may be configured as a transmitting UM RLC entity or as a receiving UM RLC entity. If the UM RLC entity is a bi-directional entity, the UM RRC entity can be configured as a UM RLC entity consisting of a transmitting side and a receiving side. The AM may divide and/or combine data received from the upper layer, add an RLC header, control data retransmission, and the like. The AM RLC entity is a bidirectional entity and can be configured as an AM RLC consisting of a transmitting side and a receiving side. Data provided to the lower layer by TM and/or data provided from the lower layer may be called TMD PDU. Data provided to lower layers in UM and/or data provided from lower layers may be referred to as UMD PDUs. Data provided to the lower layer by AM or data provided from the lower layer may be called AMD PDU. The RLC PDU format used in E-UTRA RLC and the RLC PDU format used in NR RLC can be different. RLC PDUs may include data RLC PDUs and control RLC PDUs. The RLC PDU for data may be called RLC DATA PDU (RLC Data PDU). Also, the control RLC PDU may be called an RLC CONTROL PDU.

An example of PDCP functions will be described. PDCP may be referred to as a PDCP sublayer. PDCP may have a function to maintain sequence numbers. PDCP may also have a header compression/decompression function for efficiently transmitting user data such as IP packets and Ethernet frames over a wireless section. A protocol used for IP packet header compression/decompression may be called ROHC (Robust Header Compression) protocol. Also, the protocol used for Ethernet frame header compression/decompression is EHC (Ethernet (registered trademark)
Header Compression protocol. PDCP may also have a data encryption/decryption function. PDCP may also have the function of integrity protection and integrity verification of data. PDCP may also have a re-ordering function. PDCP may also have a retransmission function for PDCP SDUs. PDCP may also have a function of discarding data using a discard timer. PDCP may also have a duplication function. In addition, PDCP may have a function of discarding duplicated received data. The PDCP entity is a bi-directional entity and can consist of a transmitting PDCP entity and a receiving PDCP entity. Also, the PDCP PDU format used in E-UTRA PDCP and the PDCP PDU format used in NR PDCP may be different. PDCP PDUs may include data PDCP PDUs and control PDCP PDUs. A PDCP PDU for data may be called a PDCP DATA PDU (PDCP Data PDU). Also, the PDCP PDU for control may be called a PDCP CONTROL PDU (PDCP Control PDU).

An example of SDAP functions will be described. SDAP is the Service Data Adaptation Protocol Layer (Service Data Adaptation Protocol Layer). SDAP is a mapping between a downlink QoS flow and a data radio bearer (DRB) sent from the 5GC 110 to the terminal device via the base station device, and/or from the terminal device via the base station device. It may have the ability to map uplink QoS flows sent to the 5GC 110 to the DRB. SDAP may also have a function to store mapping rule information. Also, SDAP may have a function of marking a QoS flow identifier (QoS Flow ID: QFI). SDAP PDUs may include data SDAP PDUs and control SDAP PDUs. A data SDAP PDU may be called an SDAP DATA PDU. Also, the control SDAP PDU may be called SDAP CONTROL PDU. Note that one SDAP entity of the terminal device may exist for each PDU session.

An example of RRC functions will be described. RRC may have a broadcast function. RRC may have a paging function from EPC 104 and/or 5GC 110 . RRC may have paging capabilities from eNB 102 connected to gNB 108 or 5GC 100 . RRC may also have an RRC connection management function. RRC may also have a radio bearer control function. RRC may also have a cell group control function. RRC may also have a mobility control function. RRC may also have terminal measurement reporting and terminal measurement reporting control functions. Also, RRC may have a QoS management function. RRC may also have radio link failure detection and recovery capabilities. RRC uses RRC messages for broadcasting, paging, RRC connection management, radio bearer control, cell group control, mobility control, terminal equipment measurement reporting and terminal equipment measurement reporting control, QoS management, radio link failure detection and recovery, etc. good to go Note that the RRC messages and parameters used in E-UTRA RRC may differ from the RRC messages and parameters used in NR RRC.

The RRC message may be sent using the logical channel's BCCH, may be sent using the logical channel's PCCH, may be sent using the logical channel's CCCH, or may be sent using the logical channel's DCCH. good to be sent

RRC messages sent using the BCCH may include, for example, a Master Information Block (MIB), each type of System Information Block (SIB), and so on. Good RRC messages included. RRC messages sent using the PCCH may include, for example, paging messages and may include other RRC messages.

RRC messages sent in the uplink (UL) direction using CCCH include, for example, RRC Setup Request, RRC Resume Request, RRC Reestablishment Request, RRC A system information request message (RRC System Info Request) may be included. Also, for example, an RRC connection request message, an RRC connection resume request message, an RRC connection reestablishment request message, etc. may be included. Also other RRC messages may be included.

RRC messages sent in the downlink (DL) direction using CCCH include, for example, RRC Connection Reject, RRC Connection Setup, RRC Connection Reestablishment, RRC A connection reestablishment rejection message (RRC Connection Reestablishment Reject) may be included. Also, for example, an RRC rejection message (RRC Reject), an RRC setup message (RRC Setup), etc. may be included. Also other RRC messages may be included.

RRC messages sent in the uplink (UL) direction using DCCH include, for example, a measurement report message, an RRC connection reconfiguration complete message (RRC Connection Reconfiguration Complete), and an RRC connection setup complete message (RRC Connection Setup Complete). , RRC Connection Reestablishment Complete message, Security Mode Complete message, UE Capability Information message, etc. may be included. Also for example measurement report message, RRC reconfiguration complete message (RRC Reconfiguration Complete), RRC setup complete message (RRC Setup Complete), RRC reestablishment complete message (RRC Reestablishment Complete), RRC resume complete message (RRC Resume Complete ), Security Mode Complete message, UE Capability Information message, etc. may be included. Also other RRC messages may be included.

RRC messages sent in the downlink (DL) direction using DCCH include, for example, an RRC connection reconfiguration message (RRC Connection Reconfiguration), an RRC connection release message (RRC Connection
Release), Security Mode Command message, UE Capability Inquiry message, etc. may be included. Also for example RRC Reconfiguration message, RRC Resume message, RRC Release message, RRC Reestablishment message, Security Mode Command message, UE Capability Inquiry message. (UE Capability Inquiry) etc. may be included. Also other RRC messages may be included.

An example of NAS functions will be described. NAS may have an authentication function. Also, the NAS may have a function to perform mobility management. Also, the NAS may have a security control function.

The functions of the PHY, MAC, RLC, PDCP, SDAP, RRC, and NAS described above are examples, and some or all of the functions may not be implemented. Also, part or all of the functions of each layer (each layer) may be included in another layer (layer).

Next, state transitions of the UE 122 in LTE and NR will be described. For UE 122 connecting to EPC or 5GC, when RRC connection has been established, UE 122 may be in RRC_CONNECTED state. A state in which an RRC connection is established may include a state in which the UE 122 holds some or all of the UE contexts described below. Also, states in which an RRC connection is established may include states in which UE 122 is able to transmit and/or receive unicast data. UE 122 may also be in RRC_INACTIVE state when the RRC connection is suspended. Also, the UE 122 may enter the RRC_INACTIVE state when the UE 122 is connected to the 5GC and the RRC connection is dormant. A UE 122 may be in the RRC_IDLE state when the UE 122 is neither in the RRC_CONNECTED state nor in the RRC_INACTIVE state.

Note that if the UE 122 is connected to the EPC, it does not have the RRC_INACTIVE state, but E-UTRAN may initiate dormancy of the RRC connection. If the UE 122 is connected to EPC, when the RRC connection is suspended, the UE 122 may retain the UE's AS context and resumeIdentity and transition to the RRC_IDLE state. A layer higher than the RRC layer of UE 122 (for example, NAS layer) confirms that UE 122 holds the AS context of the UE, and that the E-UTRAN permits recovery of the RRC connection, and that UE 122 exits the RRC_IDLE state. When it needs to transition to the RRC_CONNECTED state, it may initiate the resumption of a dormant RRC connection.

The UE 122 connected to the EPC 104 and the UE 122 connected to the 5GC 110 may have different definitions of hibernation. Also, when UE122 is connected to EPC (when UE122 is dormant in RRC_IDLE state) and when UE122 is connected to 5GC (when UE122 is dormant in RRC_INACTIVE state), UE122 all or part of the procedure for waking up from sleep may be different.

The RRC_CONNECTED state, RRC_INACTIVE state, and RRC_IDLE state may be called connected mode, inactive mode, and idle mode, respectively, and RRC connected mode. , RRC inactive mode, and RRC idle mode.

The UE AS context held by UE 122 includes the current RRC settings, current security context, PDCP state including ROHC (RObust Header Compression) state, C-RNTI (Cell Radio It may be information including all or part of a network temporary identifier), a cell identifier (cellIdentity), and a physical cell identifier of the connection source PCell. Note that the UE AS context held by either or all of the eNB 102 and gNB 108 may contain the same information as the UE AS context held by the UE 122, or the information contained in the UE AS context held by the UE 122. may contain different information.

A security context consists of a cryptographic key at the AS level, NH (Next Hop parameter), NCC (Next Hop Chaining Counter parameter) used to derive the access key for the next hop, an identifier for the selected AS level encryption algorithm, and replay protection. may be information including all or part of the counters used for

A cell group set by the base station apparatus for the terminal apparatus will be described. A cell group may consist of one special cell (Special Cell: SpCell). Also, a cell group may consist of one SpCell and one or more secondary cells (SCells). That is, a cell group may consist of one SpCell and optionally one or more SCells. A cell group may also be expressed as a set of cell(s). Note that when a MAC entity is associated with a master cell group (MCG), SpCell may mean a primary cell (PCell). Also, when the MAC entity is associated with a Secondary Cell Group (SCG), the SpCell may mean a Primary SCG Cell (PSCell). SpCell may also mean PCell if the MAC entity is not associated with a cell group. PCell, PSCell and SCell are serving cells. A SpCell may support PUCCH transmission and contention-based Random Access, and may be always activated. A PCell may be a cell used for an RRC connection establishment procedure when a terminal device in the RRC idle state transitions to the RRC connected state. Also, the PCell may be a cell used for the RRC connection re-establishment procedure in which the terminal device re-establishes the RRC connection. Also, the PCell may be a cell used for random access procedures during handover. A PSCell may be a cell used in a random access procedure when adding a secondary node (SN), which will be described later. Also, the SpCell may be a cell that is used for purposes other than those described above. It should be noted that the fact that a cell group configured for a terminal device is composed of SpCells and one or more SCells is considered to mean that carrier aggregation (CA) is configured for the terminal device. good. Also, a cell that provides an additional radio resource to a SpCell for a terminal device in which CA is configured may mean an SCell.

Timing refers to a group of serving cells configured by RRC that uses the same timing reference cell and the same timing advance value for the cells in which uplink is configured. You can call it the Advance Group (Timing Advance Group: TAG). Also, a TAG containing a MAC entity SpCell may refer to a Primary Timing Advance Group (PTAG). TAGs other than the above PTAGs may mean secondary timing advance groups (STAGs).

Also, when Dual Connectivity (DC) or Multi-Radio Dual Connectivity (MR-DC) is performed, a cell group may be added from the base station apparatus to the terminal apparatus. DC is a technique of performing data communication using radio resources of cell groups respectively configured by a first base station apparatus (first node) and a second base station apparatus (second node). good. MR-DC can be a technology included in DC. A first base station device can add a second base station device to perform DC. The first base station device may be called a master node (Master Node: MN). A cell group composed of master nodes may be called a master cell group (MCG). The second base station device may be called a secondary node (SN). A cell group formed by secondary nodes may be called a secondary cell group (SCG). Note that the master node and the secondary node may be configured within the same base station apparatus.

Also, when DC is not set, the cell group set in the terminal device may be called MCG. Also, when DC is not configured, SpCell configured in the terminal device may be PCell.

Note that MR-DC may be a technique for performing DC using E-UTRA for MCG and NR for SCG. Also, MR-DC may be a technique of performing DC using NR for MCG and E-UTRA for SCG. Also, MR-DC may be a technique of performing DC using NR for both MCG and SCG. Examples of MR-DC using E-UTRA for MCG and NR for SCG include EN-DC (E-UTRA-NR Dual Connectivity) using EPC in the core network, and NGEN-DC using 5GC in the core network. It is good to have DC (NG-RAN E-UTRA-NR Dual Connectivity). As an example of MR-DC that uses NR for MCG and E-UTRA for SCG, there may be NE-DC (NR-E-UTRA Dual Connectivity) that uses 5GC for the core network. An example of MR-DC that uses NR for both MCG and SCG may be NR-DC (NR-NR Dual Connectivity) that uses 5GC for the core network.

Note that in the terminal device, one MAC entity may exist for each cell group. For example, when DC or MR-DC is configured in the terminal device, there may be one MAC entity for MCG and one MAC entity for SCG. The MAC entity for the MCG in the terminal may always be established in the terminal in all states (RRC idle, RRC connected, RRC inactive, etc.). Also, the MAC entity for the SCG in the terminal may be created by the terminal when the SCG is configured in the terminal. Also, the MAC entity for each cell group of the terminal device may be set by the terminal device receiving an RRC message from the base station apparatus. In EN-DC and NGEN-DC, the MAC entity for MCG may be the E-UTRA MAC entity and the MAC entity for SCG may be the NR MAC entity. Also, in the NE-DC, the MAC entity for MCG may be the NR MAC entity, and the MAC entity for SCG may be the E-UTRA MAC entity. Also, in NR-DC, both MAC entities for MCG and SCG may be NR MAC entities. Note that one MAC entity exists for each cell group can be rephrased as one MAC entity exists for each SpCell. Also, one MAC entity for each cell group can be rephrased as one MAC entity for each SpCell.

A radio bearer is described. SRB0 to SRB2 may be defined as SRBs of E-UTRA, and SRBs other than these may be defined. SRB0 to SRB3 may be defined as SRBs of NR, and SRBs other than these may be defined. SRB0 may be the SRB for RRC messages transmitted and/or received using the CCCH of the logical channel. SRB1 may be the SRB for RRC messages and for NAS messages before the establishment of SRB2. RRC messages sent and/or received using SRB1 can include piggybacked NAS messages. All RRC and NAS messages sent and/or received using SRB1 can use the DCCH of the logical channel. SRB2 may be an SRB for NAS messages and for RRC messages including logged measurement information. All RRC and NAS messages transmitted and/or received using SRB2 can use the DCCH of the logical channel. Also, SRB2 may have a lower priority than SRB1. SRB3 may be an SRB for transmitting and/or receiving a specific RRC message when EN-DC, NGEN-DC, NR-DC, etc. are configured in the terminal device. All RRC and NAS messages sent and/or received using SRB3 can use the DCCH of the logical channel. Other SRBs may also be provided for other uses. A DRB may be a radio bearer for user data. Logical channel DTCH may be used for RRC messages transmitted and/or received using DRB.

A radio bearer in the terminal will be described. Radio bearers can include RLC bearers. An RLC bearer may consist of one or two RLC entities and logical channels. The RLC entity when there are two RLC entities in the RLC bearer can be a TM RLC entity and/or a transmitting RLC entity and a receiving RLC entity in a unidirectional UM mode RLC entity. SRB0 may consist of one RLC bearer. An SRB0 RLC bearer can consist of a TM RLC entity and a logical channel. SRB0 may always be established in the terminal in all states (RRC idle state, RRC connected state, RRC inactive state, etc.). One SRB1 may be established and/or configured in the terminal device by an RRC message received from the base station device when the terminal device transitions from the RRC idle state to the RRC connected state. SRB1 may consist of one PDCP entity and one or more RLC bearers. An SRB1 RLC bearer can consist of an AM RLC entity and a logical channel. One SRB2 may be established and/or configured in the terminal device by an RRC message received from the base station device by the terminal device in the RRC connected state with AS security activated. SRB2 may consist of one PDCP entity and one or more RLC bearers. An SRB2 RLC bearer can consist of an AM RLC entity and a logical channel. Note that the PDCP on the base station device side of SRB1 and SRB2 may be placed in the master node. SRB3 is when a secondary node in EN-DC, NGEN-DC, or NR-DC is added, or when the secondary node is changed, the terminal device in the RRC connection state with AS security activated is the base station. One may be established and/or configured in a terminal device by RRC messages received from the device. SRB3 may be a direct SRB between the terminal device and the secondary node. SRB3 may consist of one PDCP entity and one or more RLC bearers. An SRB3 RLC bearer can consist of an AM RLC entity and a logical channel. The PDCP on the base station device side of SRB3 can be placed in the secondary node. One or more DRBs may be established and/or configured in a terminal device by RRC messages received from the base station device by the terminal device in RRC connected state with AS security activated. A DRB may consist of one PDCP entity and one or more RLC bearers. A DRB RLC bearer may consist of an AM or UM RLC entity and a logical channel.

In MR-DC, a radio bearer in which PDCP is placed in the master node may be called a MN terminated (terminated) bearer. Also, in MR-DC, a radio bearer in which PDCP is placed in a secondary node may be called an SN terminated (terminated) bearer. In MR-DC, a radio bearer in which the RLC bearer exists only in the MCG may be called an MCG bearer. Also, in MR-DC, a radio bearer in which the RLC bearer exists only in the SCG may be called an SCG bearer. Also, in a DC, a radio bearer in which the RLC bearer exists in both the MCG and SCG may be called a split bearer.

When MR-DC is configured in the terminal device, the bearer types of SRB1 and SRB2 established/and configured in the terminal device may be MN-terminated MCG bearer and/or MN-terminated split bearer. Also, when MR-DC is configured in the terminal device, the bearer type of SRB3 established/or configured in the terminal device may be an SN-terminated SCG bearer. Also, when MR-DC is configured in the terminal device, the DRB bearer type established/and configured in the terminal device may be any of all bearer types.

For an RLC bearer established and/or configured in an E-UTRA configured cell group, the RLC entity established and/or configured may be an E-UTRA RLC. Also, for an RLC bearer established and/or configured in a group of cells configured with NR, the RLC entity established and/or configured may be an NR RLC. If the terminal is configured with EN-DC, the PDCP entity established and/or configured for the MN-terminated MCG bearer can be either E-UTRA PDCP or NR PDCP. For other bearer type radio bearers, i.e. MN terminated split bearer, MN terminated SCG bearer, SN terminated MCG bearer, SN terminated split bearer and SN terminated SCG bearer, when EN-DC is configured in the terminal equipment. The PDCP established and/or configured at the same time may be the NR PDCP. Also, when NGEN-DC, NE-DC, or NR-DC is configured in the terminal device, the PDCP entity established and/or configured for radio bearers in all bearer types may be NR PDCP. .

Note that in NR, a DRB established and/or configured in a terminal device may be associated with one PDU session. One SDAP entity may be established and/or configured for one PDU session in a terminal device. Established and/or Configured in Terminal The SDAP entity, PDCP entity, RLC entity, and logical channels can be established and/or configured by the RRC messages that the terminal receives from the base station.

Regardless of whether or not MR-DC is set, a network configuration in which the master node is eNB 102 and EPC 104 is the core network may be called E-UTRA/EPC. A network configuration in which the master node is eNB 102 and 5GC 110 is the core network can be called E-UTRA/5GC. A network configuration in which the master node is gNB 108 and 5GC 110 is the core network may be called NR or NR/5GC. When MR-DC is not configured, the above-mentioned master node may refer to a base station apparatus that communicates with terminal apparatuses.

Next, handover in LTE and NR will be explained. Handover may be the process by which a UE 122 in RRC Connected state changes its serving cell from a source SpCell to a target SpCell. Handover can occur when UE 122 receives an RRC message from eNB 102 and/or gNB 108 indicating a handover. The RRC message instructing handover may be a message regarding reconfiguration of the RRC connection that includes a parameter instructing handover (for example, an information element named MobilityControlInfo or an information element named ReconfigurationWithSync). The information element named MobilityControlInfo described above may be rephrased as a mobility control setting information element, a mobility control setting, or mobility control information. Note that the above information element named ReconfigurationWithSync may be rephrased as a reset information element with synchronization or a reset with synchronization. Also, the RRC message instructing handover may be a message indicating movement to another RAT cell (for example, MobilityFromEUTRACommand or MobilityFromNRCommand). Handover may be rephrased as reconfiguration with sync. Also, the conditions under which UE 122 can perform handover include some or all of the following: when AS security is activated, when SRB2 is established, and at least one DRB is established. good.

A flow of RRC messages transmitted and received between a terminal device and a base station device will be described. FIG. 4 is a diagram showing an example flow of procedures for various settings in RRC according to the embodiment of the present invention. FIG. 4 is an example flow when an RRC message is sent from the base station apparatus (eNB 102 and/or gNB 108) to the terminal apparatus (UE 122).

In FIG. 4, the base station device creates an RRC message (step S400). The creation of the RRC message in the base station apparatus may be performed in order for the base station apparatus to distribute system information (SI) and paging information. Also, the creation of the RRC message in the base station apparatus may be performed so that the base station apparatus causes a specific terminal apparatus to perform processing. The processing that a particular terminal device is caused to perform may include, for example, security-related configuration, RRC connection reconfiguration, handover to a different RAT, RRC connection suspension, RRC connection release, and the like. RRC connection reset processing includes, for example, radio bearer control (establishment, change, release, etc.), cell group control (establishment, addition, change, release, etc.), measurement setting, handover, security key update, etc. Good to include. Also, the creation of the RRC message in the base station device may be performed in response to the RRC message transmitted from the terminal device. Responses to RRC messages sent from the terminal may include, for example, responses to RRC setup requests, responses to RRC reconnection requests, responses to RRC resume requests, and the like. The RRC message contains information (parameters) for various information notifications and settings. These parameters may be called fields and/or information elements and may be described using the ASN.1 (Abstract Syntax Notation One) description scheme.

In FIG. 4, the base station device then transmits the created RRC message to the terminal device (step S402). Next, the terminal device performs processing such as setting according to the received RRC message, if necessary (step S404). The terminal device that has performed the processing may transmit an RRC message for response to the base station device (not shown).

RRC messages may be used for other purposes, not limited to the examples given above.

Note that in MR-DC, RRC on the master node side is used to transfer RRC messages for SCG side settings (cell group settings, radio bearer settings, measurement settings, etc.) to and from terminal devices. good. For example, in EN-DC or NGEN-DC, E-UTRA RRC messages sent and received between eNB 102 and UE 122 may include NR RRC messages in the form of containers. Also, in the NE-DC, NR RRC messages sent and received between the gNB 108 and the UE 122 may include E-UTRA RRC messages in the form of containers. RRC messages for SCG side configuration can be sent and received between the master and secondary nodes.

In addition, not only when using MR-DC, the RRC message for E-UTRA transmitted from eNB 102 to UE 122 may include the RRC message for NR, and the RRC message for NR transmitted from gNB 108 to UE 122 may be included. The message may contain an RRC message for E-UTRA.

An example of parameters included in a message regarding RRC connection reconfiguration will be described. FIG. 7 is an example of ASN.1 description representing fields and/or information elements related to cell group setting included in a message related to RRC connection reconfiguration in NR in FIG. FIG. 8 is an example of ASN.1 description representing fields and/or information elements related to cell group setting included in the message related to RRC connection reconfiguration in E-UTRA in FIG. Not limited to FIGS. 7 and 8, in the examples of ASN.1 in the embodiments of the present invention, <omitted> and <omitted> are not part of the ASN.1 notation, and other information is omitted. indicates that Information elements may be omitted even where there is no description of <omitted> or <omitted>. Note that the ASN.1 example in the embodiment of the present invention does not correctly follow the ASN.1 notation method. In the embodiment of the present invention, the example of ASN.1 represents an example of the parameters of the RRC message in the embodiment of the present invention, and other names and other representations may be used. In addition, the ASN.1 example shows only examples of main information closely related to one aspect of the present invention in order to avoid complicating the explanation. Note that all parameters described in ASN.1 may be referred to as information elements without distinguishing between fields, information elements, and the like. Further, in the embodiment of the present invention, the fields described in ASN.1, information elements, etc. included in the RRC message may be rephrased as information or parameters. Note that the message regarding RRC connection reconfiguration may be an RRC reconfiguration message in NR or an RRC connection reconfiguration message in E-UTRA.

The information element named CellGroupConfig in FIG. 7 may be an information element used for setting, changing, releasing, etc. of MCG or SCG cell groups in NR. The information element named CellGroupConfig may contain the reconfiguration with synchronization information element described below. The information element named CellGroupConfig may be rephrased as a cell group configuration information element or cell group configuration. In addition, when an information element named CellGroupConfig is used for SCG cell group configuration in NR, this information element named CellGroupConfig can be rephrased as configuration on the SCG side. An information element named SpCellConfig contained in an information element named CellGroupConfig may be an information element used to configure a particular cell (SpCell). The information element named SpCellConfig may be rephrased as SpCell configuration information element or SpCell configuration. An information element named ReconfigurationWithSync included in the information element named SpCellConfig may be an information element indicating reconfiguration with synchronization. The information element named ReconfigurationWithSync may be rephrased as a reconfiguration with synchronization information element or a reconfiguration with synchronization. Note that the information element named ReconfigurationWithSync includes a parameter for the period of a timer T304, which will be described later, indicated by t304. Also, an information element named ReconfigurationWithSync may contain parameters for performing a random access procedure indicated by RACH-ConfigDedicated.

An example of the operation of UE 122 in reconfiguration with synchronization will be described. UE 122 may initiate a random access procedure on a special cell (SpCell) if the SpCell configuration information element in the configuration on the SCG side includes reconfiguration with synchronization in MR-DC. Note that the above MR-DC may be NR-DC. Also, the special cell mentioned above may be a PSCell. Also, a message regarding re-establishment of the RRC connection may be sent on SRB1.

If the SCG-side setting that is set in the RRC connection reconfiguration message includes an information element named ReconfigurationWithSync, and the above-described random access procedure is successful, UE 122 is part of (A) to (E) below Or you can do all of them.
(A) Stop timer T304 for SCG.
(B) Stop timer T310 for the source SpCell if it is running.
(C) Inactivating SCG.
(D) SCG is considered inactive.
(E) Configure lower layers to consider the SCG to be inactive.

Note that the timer T310 may be a timer that is started when an out-of-sync instruction is received from the lower layer in the SpCell a certain number of times in succession. The lower layer mentioned above may be the physical layer.

Activation and deactivation of cells will be explained. In a terminal device that communicates with dual connectivity, a master cell group (MCG) and a secondary cell group (SCG) are set by the above-described message regarding RRC connection reconfiguration. Each cell group may consist of a special cell (SpCell) and zero or more other cells (secondary cells: SCells). SpCell of MCG is also called PCell. SpCell of SCG is also called PSCell. Cell deactivation does not apply to SpCells, but may apply to SCells.

Also, cell deactivation may not be applied to PCells, but may be applied to PSCells. In this case, cell deactivation may be performed differently for SpCells and SCells.

Cell activation and deactivation may be handled by a MAC entity that exists for each cell group. The SCell configured in the terminal device may be activated and/or deactivated by some or all of (A) to (C) below.
(A) Reception of MAC CE indicating SCell activation/deactivation
(B) SCell inactivity timer set for each SCell for which PUCCH is not set
(C) RRC parameters (sCellState) set for each SCell set in the terminal device

Specifically, the MAC entity of the terminal device may perform the following processing (AD) for each SCell configured in the cell group.

(processing AD)
If the RRC parameter (sCellState) set in the SCell when setting the SCell is set to activated, or if a MAC CE that activates the SCell is received, the MAC entity of UE 122 processes (AD-1) I do. Otherwise, if a MAC CE is received to deactivate the SCell or if the SCell inactivity timer expires in an active SCell, the MAC entity of UE 122 performs processing (AD-2). If an uplink grant or downlink allocation for an active SCell is signaled by the PDCCH of an active SCell, or if an uplink grant or downlink allocation for an active SCell is signaled by the PDCCH of a serving cell, or Once a MAC PDU has been sent on a new uplink grant or received on a configured downlink allocation, the MAC entity of UE 122 restarts the SCell inactivity timer associated with that SCell. If the SCell becomes inactive, the MAC entity of UE 122 performs processing (AD-3).

(Processing AD-1)
If, in NR, this SCell was in an inactive state before receiving the MAC CE that activates this SCell, or if the RRC parameter (sCellState) set in that SCell when setting up the SCell is set to activated If so, the MAC entity of UE 122 performs processing (AD-1A) or processing (AD-1B).
The MAC entity of UE 122 also starts or restarts (if already started) the SCell inactivity timer associated with that SCell.
If the Active DL BWP is not a dormant BWP (Dormant BWP) described later, the MAC entity of UE 122 performs some or all of (A) to (B) below.
(A) (re)initialize all suspended configured uplink grants of grant type 1 associated with this SCell according to the stored configuration, if any;
(B) Trigger PHR.
If a MAC CE for activating a SCell is received, and the BWP indicated by the first active downlink BWP identifier (firstActiveDownlinkBWP-Id) set in the RRC message for that SCell is set to a dormant BWP. If not, the UE 122 MAC entity will process (AD-1
Do A). If a MAC CE for activating a SCell is received, and the BWP indicated by the first active downlink BWP identifier (firstActiveDownlinkBWP-Id) set in the RRC message for that SCell is set to a dormant BWP. If so, the MAC entity of UE 122 takes action (AD-1B). Also, the MAC entity of UE 122 implements some or all of (A) to (B) below.
(A) Activate the BWP indicated by the first active downlink BWP identifier (firstActiveDownlinkBWP-Id) set in the RRC message
(B) Activate the BWP indicated by the first active uplink BWP identifier (firstActiveUplinkBWP-Id) set in the RRC message

(Processing AD-1A)
The MAC entity of UE 122 activates the SCell and applies (performs) normal SCell operations including some or all of (A) to (E) below.
(A) Transmission of Sounding Reference Signals (SRS) in this SCell
(B) reporting channel state information (CSI) for this SCell;
(C) Monitor PDCCH in this SCell
(D) PDCCH monitoring for this SCell (if scheduling for this SCell is performed in another serving cell)
(E) If PUCCH is configured, PUCCH transmission on this SCell

(Processing AD-1B)
UE 122's MAC entity stops the BWP inactivity timer for this serving cell if it is running.

(Processing AD-2)
The MAC entity of UE 122 performs some or all of (A) through (F) below.
(A) Inactivating this SCell.
(B) Stop the SCell inactivity timer associated with this SCell.
(C) Inactivate all activated BWPs associated with this SCell.
(D) Clear all configured downlink assignments and/or all grant type 2 configured uplink grants associated with this SCell.
(E) Suspend all configured uplink grants of grant type 1 associated with this SCell.
(F) Flush the HARQ buffer associated with this SCell.

(Processing AD-3)
The MAC entity of UE 122 performs some or all of (A) through (D) below.
(A) Do not transmit SRS on this SCell.
(B) Do not report CSI for this SCell.
(C) Do not transmit PUCCH, UL-SCH and/or RACH on this SCell.
(D) Do not monitor the PDCCH of this SCell and/or the PDCCH for this SCell.

As described above, the MAC entity performs processing (AD) to activate and deactivate the SCell.

Also, when the SCell is added as described above, the initial state of the SCell may be set by the RRC message.

Here, the SCell inactivity timer will be described. For SCells for which PUCCH is not configured, the value of the SCell inactivity timer (information regarding the time when the timer is considered to have expired) may be notified by the RRC message. For example, when information indicating 40 ms is notified as the value of the SCell inactivity timer in the RRC message, the time notified without stopping the timer after starting or restarting the timer in the above process (AD) (here 40ms) has elapsed, the timer is considered expired. The SCell deactivation timer may also be a timer named sCellDeactivationTimer.

Here, the band part (BWP) will be explained.

The BWP may be part or all of the bandwidth of the serving cell. A BWP may also be called a carrier BWP. A terminal device may be configured with one or more BWPs. A certain BWP may be set by information included in the broadcast information associated with the synchronization signal detected in the initial cell search. Also, a certain BWP may be a frequency bandwidth associated with a frequency for initial cell search. A certain BWP may also be configured with RRC signaling (eg, Dedicated RRC signaling). Also, the downlink BWP (DL BWP) and the uplink BWP (UL BWP) may be configured separately. Also, one or more uplink BWPs may be associated with one or more downlink BWPs. Further, the association between the uplink BWP and the downlink BWP may be a default association, may be an association by RRC signaling (eg Dedicated RRC signaling), physical layer signaling (eg downlink The association may be based on downlink control information (DCI) notified by a control channel, or a combination thereof.

A BWP may consist of a group of contiguous physical radio blocks (PRBs). Also, parameters of the BWP (one or more BWPs) of each component carrier may be set for the terminal device in the connected state. The BWP parameters for each component carrier include (A) the type of cyclic prefix, (B) the subcarrier spacing, (C) the frequency position of the BWP (for example, the start position or center frequency position on the low frequency side of the BWP) ( For the frequency position, for example, ARFCN may be used, or an offset from a specific subcarrier of the serving cell may be used.In addition, the offset unit may be a subcarrier unit or a resource block unit. Also, both ARFCN and offset may be set.), (D) BWP bandwidth (e.g. number of PRBs), (E) control signal resource configuration information, (F) SS block center frequency. For the position (frequency position, for example, ARFCN may be used, or an offset from a specific subcarrier of the serving cell may be used.In addition, the offset unit may be a subcarrier unit, or a resource block unit, and both ARFCN and offset may be set.), may be included. Also, the resource configuration information of the control signal may be included in the BWP configuration of at least some or all of the PCell and/or PSCell.

The terminal device may perform transmission/reception in an active BWP (Active BWP) among one or more set BWPs. Among one or more BWPs configured for one serving cell associated with a terminal device, at most one uplink BWP and/or at most one downlink BWP is active at a given time. It may be set to be BWP. The activated downlink BWP is also called Active DL BWP. The activated uplink BWP is also called Active UL BWP.

Next, the inactivation of BWP will be explained. One or more BWPs may be configured in one serving cell. BWP switching in the serving cell is used to activate inactivated BWPs (also called inactive BWPs) and deactivate BWPs that have been activated.

BWP switching is controlled by the MAC entity itself for PDCCH indicating downlink assignment or uplink grant, BWP inactivity timer, RRC signaling, or initiation of random access procedure. Active BWP of the serving cell is indicated by RRC or PDCCH.

Next, a random access procedure in the UE with BWP set will be described. When initiating a random access procedure in a serving cell, the MAC entity performs some or all of the following (A) to (E) on the selected carrier of this serving cell.
(Processing BRA)
(A) If the PRACH transmission resource (occasion) is not set for the Active UL BWP, (A1) switch the Active UL BWP to the BWP indicated by the RRC parameter (initialUplinkBWP), and (A2) If the serving cell is a SpCell, switch the Active UL BWP to the BWP indicated by the RRC parameter initialDownlinkBWP.
(B) If the resource (occasion) for transmitting PRACH is configured for Active UL BWP, if the serving cell is SpCell and Active DL BWP and Active UL BWP have the same identifier (bwp-Id) If not, switch the Active DL BWP to a BWP with the same identifier as the Active UL BWP.
(C) If the BWP inactivity timer associated with this serving cell's Active DL BWP is running, stop this timer.
(D) If the serving cell is a SCell, stop the BWP inactivity timer associated with the SpCell's Active DL BWP if it is running.
(E) Execute a random access procedure on the SpCell's Active DL BWP and this serving cell's Active UL BWP.

Next, the BWP inactivity timer will be described. The MAC entity performs the following processing (A) for each activated serving cell for which the BWP inactivity timer is set. The BWP inactivity timer may also be a timer named bwp-InactivityTimer.
(A) If the default downlink BWP identifier (defaultDownlinkBWP-Id) is configured and the Active DL BWP is not the BWP indicated by the identifier (dormantDownlinkBWP-Id), or if the default downlink BWP identifier (defaultDownlinkBWP-Id ) is not set, the Active DL BWP is not the initialDownlinkBWP, and the Active DL BWP is not the BWP indicated by the identifier (dormantDownlinkBWP-Id), the MAC entity performs the following processing (B) and (D).
(B) if a PDCCH addressed to C-RNTI or CS-RNTI indicating downlink assignment or uplink grant is received in Active DL BWP, or if for Active DL BWP, Received PDCCH addressed to C-RNTI or CS-RNTI indicating downlink assignment or uplink grant or if MAC PDU was sent with configured uplink grant or configured downlink If a MAC PDU is received for assignment, the MAC entity performs the following (C).
(C) if no random access procedure associated with this serving cell is in progress, or an ongoing random access procedure associated with this serving cell is successfully completed upon receipt of a PDCCH addressed to C-RNTI; Once (Successfully completed), start or restart the BWP inactivity timer associated with the Active DL BWP.
(D) If the BWP inactivity timer associated with the Active DL BWP expires, the MAC entity performs the following (E).
(E) If defaultDownlinkBWP-Id is set, perform BWP switching to the BWP indicated by this defaultDownlinkBWP-Id; otherwise, perform BWP switching to initialDownlinkBWP.

Also, if the MAC entity receives the PDCCH for BWP switching and switches the Active DL BWP, it performs the following processing (A).
(A) If the default downlink BWP identifier (defaultDownlinkBWP-Id) is set, the switched Active DL BWP is not the BWP indicated by the identifier (dormantDownlinkBWP-Id), and if the switched Active DL BWP is dormantDownlinkBWP- If not the BWP indicated by Id, start or restart the BWP inactivity timer associated with the Active DL BWP.

Next, deactivation of SCG will be described.

Inactivation of SCG may mean inactivation of SCG. Also, deactivating an SCG may mean deactivating a cell group in which a MAC entity is associated with the SCG and corresponds to the MAC entity. Activation of SCG may mean activation of SCG. Also, activating an SCG may mean activating a cell group in which a MAC entity is associated with the SCG and corresponds to the MAC entity.

In LTE and/or NR, the state in which the SCG is inactivated (the state in which the SCG is dormant) means that the terminal device performs one of the following (A) to (K) in the SCG SpCell (PSCell). It may be in a state of implementing part or all.
(SD-1)
(A) Do not transmit SRS on this SpCell.
(B) Measure CSI for this SpCell.
(C) Do not report CSI for this SpCell.
(D) Do not transmit PUCCH, UL-SCH and/or RACH on this SpCell.
(E) Do not monitor the PDCCH for this SpCell and/or the PDCCH for this SpCell.
(F) Perform discontinuous reception (DRX) in this SpCell.
(G) PDCCH for this SpCell and/or addressed to C-RNTI, MCS-C-RNTI and/or CS-RNTI indicating uplink grant for UL-SCH transmission on this SpCell; Do not monitor PDCCH for
(H) PDCCH for this SpCell with BWP activated and addressed to C-RNTI, MCS-C-RNTI and/or CS-RNTI indicating uplink grant in said BWP; and / Or do not monitor the PDCCH for this SpCell.
(I) Automatic Gain Control (AGC), beam management, including beam failure recovery, and/or radio link monitoring (Radio Link Monitoring) in this SpCell
Monitoring: RLM).
(J) Leave suspended some or all configured uplink grants of grant type 1 associated with this SpCell.
(K) Maintain the timeAlignmentTimer (TAT) associated with the TAG (PTAG) containing this SpCell.

In LTE and/or NR, the state in which the SCG is activated (the state in which the SCG is not dormant) means that the terminal device performs part of (A) to (K) below in the SCG SpCell (PSCell) Or it may be in a state of implementing all.
(SA-1)
(A) Send SRS on this SpCell.
(B) Measure CSI for this SpCell.
(C) Report CSI for this SpCell.
(D) Transmit PUCCH, UL-SCH and/or RACH on this SpCell.
(E) Monitor the PDCCH for this SpCell and/or the PDCCH for this SpCell.
(F) Perform discontinuous reception (DRX) in this SpCell.
(G) PDCCH for this SpCell and/or addressed to C-RNTI, MCS-C-RNTI and/or CS-RNTI indicating uplink grant for UL-SCH transmission on this SpCell; monitor the PDCCH for
(H) PDCCH for this SpCell with BWP activated and addressed to C-RNTI, MCS-C-RNTI and/or CS-RNTI indicating uplink grant in said BWP; and / Or monitor the PDCCH for this SpCell.
(I) Automatic Gain Control (AGC), beam management, including beam failure recovery, and/or radio link monitoring (Radio Link Monitoring) in this SpCell
Monitoring: RLM).
(J) Maintain some or all configured uplink grants of grant type 1 associated with this SpCell.
(K) Maintain the timeAlignmentTimer (TAT) associated with the TAG (PTAG) containing this SpCell.

In LTE and/or NR, the terminal device may determine that the SCG will be deactivated based on some or all of (A) to (H) below. Note that the messages and control elements (A) to (F) below may be notified to the terminal device from a cell group other than the SCG.
(SD-2)
(A) Receipt of RRC message instructing deactivation of SCG
(B) Receipt of MAC control element indicating deactivation of SCG
(C) Receipt of RRC message instructing SpCell deactivation
(D) Receipt of MAC control element instructing SpCell deactivation
(E) Receipt of other RRC messages
(F) Receipt of other MAC control elements
(G) Expiration of SCG inactivity timer
(H) Expiration of PSCell inactivity timer

FIG. 11 is a diagram showing an example of an embodiment. In FIG. 11, the processing unit 502 of the UE 122 determines that the SCG becomes inactive based on (SD-2) above (step S1100). Also, the processing unit 502 of the UE 122 operates in the inactive state based on the determination (step S1102).

In LTE and/or NR, the terminal device may determine that the SCG is not deactivated based on some or all of (A) to (K) below. Note that the messages and control elements (A) to (F) below may be notified to the terminal device from a cell group other than the SCG. The fact that the SCG is not in an inactive state may mean that the SCG is in an active state.
(SA-2)
(A) Receipt of RRC message indicating activation of SCG
(B) Receipt of MAC control element indicating activation of SCG
(C) Receipt of RRC message instructing activation of SpCell
(D) Receipt of MAC control element instructing activation of SpCell
(E) Receipt of other RRC messages
(F) Receipt of other MAC control elements
(G) SCG inactivity timer
(H)PSCell inactivity timer
(I) Start of random access procedure due to scheduling request triggered to send MAC PDU containing MAC SDU
(J) Start of random access procedure
(K) Initiation of a random access procedure resulting from a scheduling request (in other words, initiated by the MAC entity itself)

FIG. 10 is a diagram showing an example of an embodiment. In FIG. 10, processing unit 502 of UE 122 determines that the SCG is not inactive based on (SA-2) above (step S1000). Also, the processing unit 502 of the UE 122 operates in the active state based on the determination (step S1002).

A terminal device that performs SCG deactivation may perform some or all of the following processes (A) to (F) in the SCG.
(SD-3)
(A) All SCells are inactivated.
(B) Assume that all of the SCell inactivity timers associated with the active SCell have expired.
(C) Assume that all SCell inactivity timers associated with the dormant SCell have expired.
(D) Do not start or restart the SCell inactivity timers associated with all SCells.
(E) Ignore MAC CEs that activate SCells. For example, in the processing (AD), when MAC CE for activating SCell is received and SCG deactivation is not instructed (or SCG is not inactive), processing (AD-1 )I do.
(F) Execute the above process (AD-2). For example, when SCG is instructed to be inactivated (or SCG becomes inactive) in the processing (AD-2), processing (AD-2) is performed.

A terminal device that activates an SCG may perform the following processes (A) and/or (B) in the SCG.
(SA-3)
(A) Execute processing (AD-1) to activate all SCells.
(B) If the activation of the SCG is performed based on the RRC message, if this RRC message contains parameters related to random access to SpCell (PSCell), based on the notified parameters, the random access procedure in this SpCell Start.

FIG. 9 is a diagram showing an example of an embodiment. In FIG. 9, UE 122 receives a message (RRC message) notifying that SCG is to be inactive (dormant state) from eNB 102 or gNB 108 (step S900). Based on the notification, the UE 122 controls some or all of the cells (that is, SCells) other than the SCG SpCell (second cell) to be inactive (step S902).

By the above operation, in the process of deactivating the SCG, the transmitting unit 504 of the UE 122 is in an efficient state without independently transmitting the MAC CE for changing the SCell state of the SCG to the inactive state. change is possible. Further, when deactivation of the SCG is performed based on the RRC message, conventionally, the initial state is set in the RRC layer, and the state change is performed in the MAC layer. It is possible to efficiently change the state of the SCG while avoiding a mismatch between the instruction and the MAC layer instruction.

Based on the above description, various embodiments of the present invention will be described. In addition, each process demonstrated above may be applied about each process abbreviate|omitted by the following description.

FIG. 5 is a block diagram showing the configuration of the terminal device (UE 122) according to the embodiment of the present invention. In order to avoid complicating the description, FIG. 5 shows only main components closely related to one embodiment of the present invention.

UE 122 shown in FIG. 5 includes a receiving unit 500 that receives an RRC message or the like from a base station device, a processing unit 502 that performs processing according to parameters included in the received message, and a transmitting unit that transmits the RRC message or the like to the base station device. 504, consisting of The base station apparatus described above may be eNB 102 or gNB 108 . Also, processing unit 502 may include some or all of the functionality of various layers (eg, physical layer, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, and NAS layer). That is, the processing unit 502 includes part or all of the physical layer processing unit, MAC layer processing unit, RLC layer processing unit, PDCP layer processing unit, SDAP processing unit, RRC layer processing unit, and NAS layer processing unit. you can

FIG. 6 is a block diagram showing the configuration of the base station apparatus according to the embodiment of the present invention. In order to avoid complicating the description, FIG. 6 shows only main components closely related to one embodiment of the present invention. The base station apparatus described above may be eNB 102 or gNB 108 .

The base station apparatus shown in FIG. 6 includes a transmission unit 600 that transmits an RRC message and the like to UE 122, and a processing unit that creates an RRC message including parameters and transmits it to UE 122, thereby allowing processing unit 502 of UE 122 to perform processing. 602 and a receiver 604 that receives RRC messages and the like from the UE 122 . Also, processing unit 602 may include some or all of the functionality of various layers (eg, physical layer, MAC layer, RLC layer, PDCP layer, SDAP layer, RRC layer, and NAS layer). That is, the processing unit 602 includes part or all of the physical layer processing unit, MAC layer processing unit, RLC layer processing unit, PDCP layer processing unit, SDAP processing unit, RRC layer processing unit, and NAS layer processing unit. you can

An example of processing of the terminal device according to the embodiment of the present invention will be described with reference to FIG. By the processing of the terminal device according to the embodiment of the present invention, which will be described with reference to FIG. 10, for example, the terminal device does not need to monitor a plurality of cell groups and power consumption can be reduced. be done.

FIG. 10 is a diagram showing an example of processing of the terminal device according to the embodiment of the present invention. The processing unit 502 of the UE 122 may determine that the SCG will not become inactive based on (SA-2) above (step S1000). Also, the processing unit 502 of the UE 122 may operate in the active state based on the determination (step S1002).

An example of the operation of UE 122 in the active state will now be described. The UE 122, in the active state, may perform part or all of the processing shown in (SA-1) above in each of the SpCells and/or one or more SCells of a certain cell group.

The active state may be a state in which the SCG is activated. Also, the active state described above may be a state in which the SCG has resumed from a dormant state. Also, the active state described above may be a state in which the SCG described above is not in a dormant state. Also, the active state described above may be the transition state from the inactive state when a random access procedure due to a scheduling request triggered to transmit a MAC PDU containing a MAC SDU is initiated. . Also, the active state described above may be a state that transitions from the inactive state when the RRC entity instructs to return from the dormant state.

In step S1000, the processing unit 502 of the UE 122 may determine when the SCG has completed the transition from the inactive state to the active state. Also, the processing unit 502 of the UE 122 may determine the transition while the SCG transitions from the inactive state to the active state.

Upon receiving information to activate the SCG, UE 122 may transition the SCG from the inactive state to the active state (in other words, activate the SCG). Also, upon receiving information instructing the SCG to return from the dormant state (Resume), the UE 122 may cause the SCG to transition from the inactive state to the active state. Also, upon receiving information instructing the SpCell to return from the dormant state, the UE 122 may cause the SCG to transition from the inactive state to the active state. UE 122 may also transition the SCG from the inactive state to the active state upon receiving other information. Also, the UE 122 may transition the SCG from the inactive state to the active state based on the SCG dormancy timer. Also, the UE 122 may transition the SCG from the inactive state to the active state based on the PSCell sleep timer. UE 122 may also transition the SCG from the inactive state to the active state when initiating a random access procedure due to a scheduling request triggered to send a MAC PDU containing a MAC SDU. Also, the UE 122 may transition the SCG from the inactive state to the active state when starting the random access procedure. The UE 122 may also transition the SCG from inactive to active when initiating a random access procedure resulting from a scheduling request (in other words, initiated by the MAC entity itself). The MAC entity of UE 122 may also obtain an indication to activate an SCG, an indication to wake from a dormant SCG, an indication to wake SpCell from dormancy, and/or other information from the RRC entity of UE 122. . In addition, after the MAC entity obtains the information from the RRC entity, UE 122 determines that the SCG does not become inactive as shown in (SA-2) above, and changes the SCG from inactive to active. You can transition to The UE 122 may perform the processing shown in (SA-3) above when making the SCG transition from the inactive state to the active state.

An example of processing of the terminal device according to the embodiment of the present invention will be described with reference to FIG.

FIG. 11 is a diagram showing an example of processing of the terminal device according to the embodiment of the present invention. The processing unit 502 of the UE 122 may determine that the SCG becomes inactive based on (SD-2) above (step S1100). Also, the processing unit 502 of the UE 122 may operate in the inactive state based on the determination (step S1102).

An example of the operation of UE 122 in the inactive state described above will now be described. In the inactive state, UE 122 may perform some or all of the processing as indicated in (SD-1) above in an SpCell and/or one or more SCells of a cell group.

The inactive state may be a state in which the SCG is inactivated. Also, the inactive state described above may be Entering a dormant SCG. Also, the inactive state described above may be the dormant state of the SCG described above. The inactive state may also be a state in which the SpCell of the SCG and/or the Active BWP of one or more SCells are dormant BWPs. Also, the inactive state described above may be a transition state from the active state when a random access procedure due to a scheduling request triggered to transmit a MAC PDU containing a MAC SDU is initiated. . Also, the inactive state described above may be a state transitioned from the active state when the RRC entity instructs to enter the dormant state.

In step S1100, the processing unit 502 of the UE 122 may determine when the SCG has completed the transition from the active state to the inactive state. Also, the processing unit 502 of the UE 122 may determine the transition while the SCG transitions from the active state to the inactive state.

UE 122 may transition the SCG from the active state to the inactive state upon receiving information indicating deactivation of the SCG. Also, upon receiving information instructing entry into the dormant SCG, the UE 122 may transition the SCG from the active state to the inactive state. Also, upon receiving information instructing SpCell dormancy, the UE 122 may transition the SCG from the active state to the inactive state. UE 122 may also transition the SCG from the active state to the inactive state upon receiving other information. Also, the UE 122 may cause the SCG to transition from the active state to the inactive state when the SCG dormancy timer expires. Also, the UE 122 may transition the SCG from the active state to the inactive state when the PSCell sleep timer expires. In addition, the MAC entity of UE 122 gives an instruction to deactivate the SCG, an instruction to enter the dormant SCG, an instruction to dormant SpCell,
and/or other information may be obtained from the UE 122's RRC entity. In addition, after the MAC entity obtains the information from the RRC entity, UE 122 determines that the SCG becomes inactive as shown in (SD-2) above, and changes the SCG from active to inactive state. You can transition. The UE 122 may perform the processing shown in (SD-3) above when making the SCG transition from the active state to the inactive state.

An example of processing of the terminal device according to the embodiment of the present invention will be described with reference to FIG.

FIG. 12 is a diagram showing an example of processing of the terminal device according to the embodiment of the present invention. The processing unit 502 of the UE 122, when the SpCell configuration information element of the SCG in the message regarding the reconfiguration of the RRC connection received by the UE 122 includes reconfiguration with synchronization (step S1200), randomly accesses the PSCell included in this SCG. The procedure may start (step S1202). Also, the processing unit 502 of the UE 122 does not need to deactivate the SCG when the message regarding reconfiguration of the RRC connection does not include an instruction to deactivate the SCG (step S1200). Further, when the message regarding reconfiguration of the RRC connection includes an instruction to deactivate the SCG (step S1200), processing section 502 of UE 122 deactivates this SCG after the above-described random access procedure (step S1202) succeeds. It may be deactivated (step S1204). Note that the SpCell configuration information element of the SCG described above may be SpCellConfig included in CellGroupConfig that configures the SCG shown in FIG. Also, an instruction to deactivate the SCG described above may be included in the RRC message. Also, the above-mentioned SCG deactivation instruction may be identified by the type of RRC message (the RRC message itself). Also, the above-mentioned SCG deactivation instruction may be included in the cell group configuration information element or the SpCell configuration information element in the RRC reconfiguration message. Also, the instruction to deactivate the SCG described above may be included in an information element other than the cell group configuration information element or the SpCell configuration information element in the RRC reconfiguration message.

An example of random access procedure processing in step S1202 will be described. If the SpCell configuration information element of the SCG in the message about reconfiguration of the RRC connection received by UE122 in step S1200 includes reconfiguration with synchronization, UE122, when starting the random access procedure, in the above (RA) Processing as indicated may be performed.

An example of the SCG deactivation process in step S1204 will be described. If the message regarding RRC connection reconfiguration received by UE 122 in step S1200 includes an instruction to deactivate the SCG, processing section 502 of UE 122 may determine that the SCG is deactivated. Also, based on the determination, the UE 122 may execute the process shown in (SD-3) above after the random access procedure in step S1202 is successful. That is, the SCG may be deactivated after the random access procedure in step S1202 is successful. Further, when the message regarding reconfiguration of the RRC connection received by UE 122 in step S1200 does not include an instruction to deactivate the SCG, processing section 502 of UE 122 determines that the SCG will not be deactivated. good.

Thus, embodiments of the present invention can trigger necessary uplink transmissions even in the SCG inactive state. In addition, power can be saved by monitoring only necessary signals while the SCG is inactive.

The radio bearers in the above description can be DRB, SRB, or DRB and SRB, respectively.

Moreover, in the above description, expressions such as “link”, “associate”, and “associate” may be replaced with each other.

Moreover, in the above description, expressions such as “included”, “contained”, and “was included” may be exchanged for each other.

Further, in the above description, "above-mentioned" may be replaced with "above-mentioned".

Also, in the above description, "SCG SpCell" may be replaced with "PSCell".

In the above description, the expressions such as "determined as", "set as", and "including" may be replaced with each other.

In the above description, the "dormant state" may be replaced with the "inactive state", and the "state recovered from the dormant state" may be replaced with the "active state". In the above description, "activation" and "inactivation" may be replaced with "active state" and "inactive state", respectively.

In the above description, "transition from X to Y" may be rephrased as "transition from X to Y". Moreover, in the above description, "make a transition" may be rephrased as "determine a transition". Also, "activated BWP" may be replaced with "Active BWP".

Also, in the examples of each process or the example of the flow of each process in the above description, some or all of the steps may not be executed. In addition, the order of the steps may be different in the example of each process or the example of the flow of each process in the above description. Also, in the examples of each process or the example of the flow of each process in the above description, some or all of the processes in each step may not be executed. Further, in the example of each process or the example of the flow of each process in the above description, the order of the processes in each step may be different. Also, in the above description, "perform B based on A" may be rephrased as "perform B." That is, "doing B" may be performed independently of "being A".

In the above description, "A may be rephrased as B" may include rephrasing B as A in addition to rephrasing A as B. Further, in the above description, when "C may be D" and "C may be E" are described, "D may be E" may be included. Further, in the above description, when "F may be G" and "G may be H" are stated, "F may be H" may be included.

Also, in the above explanation, if the condition "A" and the condition "B" are contradictory conditions, the condition "B" may be expressed as the "other" condition of the condition "A". good.

Various aspects of terminal devices and methods in embodiments of the present invention are described below.

(1) A first embodiment of the present invention is a terminal device that communicates with a base station device, comprising: a receiving unit that receives an RRC message from the base station device; performs communication using a first cell group and a second cell group, wherein the RRC message includes a first configuration for configuring a special cell included in the second cell group; A unit initiates a random access procedure in the special cell based on that the first configuration includes reconfiguration with synchronization, and the processing unit includes in the RRC message the second cell group the second cell group is not deactivated if the instruction to deactivate the second cell group is not included, and the processing unit causes the RRC message to deactivate the second cell group If an indication is included, the terminal device deactivates the second cell group after the random access procedure is successful.

(2) A second embodiment of the present invention is a base station apparatus that communicates with a terminal device, comprising: a transmission unit that transmits an RRC message to the terminal device; , communicating using a first cell group and a second cell group, wherein the RRC message includes a first configuration for configuring a special cell included in the second cell group, the processing unit causes the terminal device to start a random access procedure in the special cell based on the fact that the first configuration includes reconfiguration with synchronization, and the processing unit causes the RRC message to include the If the instruction to deactivate the second cell group is not included, the processing unit does not instruct the terminal device to deactivate the second cell group, If the RRC message includes an instruction to deactivate the second cell group, cause the terminal device to deactivate the second cell group after the random access procedure is successful. It is a base station device that gives instructions for

(3) A third embodiment of the present invention is a method for a terminal device that communicates with a base station device, receiving an RRC message from the base station device, Communication is performed using a group, the RRC message includes a first configuration for configuring a special cell included in the second cell group, and the first configuration includes reconfiguration with synchronization. based on the fact that a random access procedure is initiated in the special cell, and if the RRC message does not contain an indication to deactivate the second cell group, the second cell group is If not deactivated and the RRC message includes an instruction to deactivate the second cell group, deactivate the second cell group after the random access procedure is successful. It is a method to let

(4) A fourth embodiment of the present invention is a method for a base station apparatus that communicates with a terminal apparatus, transmitting an RRC message to the terminal apparatus, and the RRC message includes a first configuration that configures a special cell included in the second cell group, and the first configuration includes reconfiguration with synchronization. Based on that, if the terminal device initiates a random access procedure in the special cell and the RRC message does not contain an instruction to deactivate the second cell group, the terminal If the device is not instructed to deactivate the second cell group and the RRC message includes an instruction to deactivate the second cell group, the random access A method of instructing the terminal device to deactivate the second cell group after the procedure is successful.

The program that runs on the apparatus according to the present invention may be a program that controls a Central Processing Unit (CPU) or the like to function a computer so as to implement the functions of the above-described embodiments of the present invention. The program or information handled by the program is temporarily read into volatile memory such as random access memory (RAM) during processing, or stored in non-volatile memory such as flash memory or hard disk drive (HDD), and stored as necessary. The CPU reads, modifies, and writes accordingly.

It should be noted that part of the devices in the above-described embodiments may be realized by a computer. In that case, the program for realizing this control function may be recorded in a computer-readable recording medium, and the program recorded in this recording medium may be read into a computer system and executed. . The "computer system" here is a computer system built in the device, and includes hardware such as an operating system and peripheral devices. Further, the "computer-readable recording medium" may be any of a semiconductor recording medium, an optical recording medium, a magnetic recording medium, and the like.

Furthermore, "computer-readable recording medium" means a medium that dynamically stores programs for a short period of time, such as a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line. , such as a volatile memory inside a computer system serving as a server or a client in that case, which holds the program for a certain period of time. Further, the program may be for realizing part of the functions described above, or may be capable of realizing the functions described above in combination with a program already recorded in the computer system.

Also, each functional block, or feature, of the apparatus used in the embodiments described above may be implemented or performed in an electrical circuit, typically an integrated circuit or multiple integrated circuits. Electrical circuits designed to perform the functions described herein may be general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or combinations thereof. A general purpose processor may be a microprocessor, in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The general-purpose processor or each circuit described above may be composed of digital circuits or may be composed of analog circuits. In addition, when an integrated circuit technology that replaces current integrated circuits emerges due to advances in semiconductor technology, it is also possible to use integrated circuits based on this technology.

It should be noted that the present invention is not limited to the above-described embodiments. In the embodiments, an example of the device was described, but the present invention is not limited to this, but stationary or non-movable electronic devices installed indoors and outdoors, such as AV equipment, kitchen equipment, It can be applied to terminal devices or communication devices such as cleaning/washing equipment, air conditioning equipment, office equipment, vending machines, and other household equipment.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like are included within the scope of the gist of the present invention. . In addition, the present invention can be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention. be Further, it also includes a configuration in which the elements described in the above embodiments are replaced with the elements having the same effect.

100 E-UTRA
102 eNB
104 EPCs
106NR
108 gNB
110 5GC
112, 114, 116, 118, 120, 124 interfaces
122 UEs
200, 300 PHYs
202, 302 MACs
204, 304 RLC
206, 306 PDCP
208, 308 RRC
310 SDAP
210, 312 NAS
500, 604 receiver
502, 602 processor
504, 600 transmitter

Claims (4)

A terminal device that communicates with a base station device,
A receiving unit for receiving an RRC message from the base station device, and a processing unit,
The processing unit communicates using a first cell group and a second cell group,
The RRC message includes a first configuration that configures a special cell included in the second cell group,
The processing unit initiates a random access procedure in the special cell based on the fact that the first configuration includes reconfiguration with synchronization,
The processing unit, if the RRC message does not include an instruction to deactivate the second cell group,
without inactivating the second cell group,
The processing unit, if the RRC message includes an instruction to deactivate the second cell group,
After the random access procedure is successful,
A terminal device that deactivates the second cell group. A base station device that communicates with a terminal device,
A transmission unit for transmitting an RRC message to the terminal device, and a processing unit,
The processing unit communicates using a first cell group and a second cell group,
The RRC message includes a first configuration that configures a special cell included in the second cell group,
The processing unit causes the terminal device to start a random access procedure in the special cell based on the fact that the first configuration includes reconfiguration with synchronization,
The processing unit, if the RRC message does not include an instruction to deactivate the second cell group,
without instructing the terminal device to deactivate the second cell group,
The processing unit, if the RRC message includes an instruction to deactivate the second cell group,
After the random access procedure is successful,
A base station apparatus that instructs the terminal apparatus to deactivate the second cell group. A method for a terminal device communicating with a base station device, comprising:
receive an RRC message from the base station device;
communicating using a first cell group and a second cell group;
The RRC message includes a first configuration that configures a special cell included in the second cell group,
starting a random access procedure in the special cell based on the first configuration including reconfiguration with synchronization;
If the RRC message does not contain an instruction to deactivate the second cell group,
without inactivating the second cell group,
If the RRC message includes an instruction to deactivate the second cell group,
After the random access procedure is successful,
A method of inactivating the second cell group. A method for a base station device communicating with a terminal device, comprising:
sending an RRC message to the terminal device;
communicating using a first cell group and a second cell group;
The RRC message includes a first configuration that configures a special cell included in the second cell group,
causing the terminal device to initiate a random access procedure in the special cell based on the fact that the first configuration includes reconfiguration with synchronization;
If the RRC message does not contain an instruction to deactivate the second cell group,
without instructing the terminal device to deactivate the second cell group,
If the RRC message includes an instruction to deactivate the second cell group,
After the random access procedure is successful,
A method of instructing the terminal device to deactivate the second cell group.

Images